James Abbott McNeil Whistler (; July 11, 1834 – July 17, 1903) was an American artist, active during the American Gilded Age and based primarily in the United Kingdom. He was averse to sentimentality and moral allusion in painting, and was a leading proponent of the credo "art for art's sake". His famous signature for his paintings was in the shape of a stylised butterfly possessing a long stinger for a tail. The symbol was apt, for it combined both aspects of his personality: his art is characterised by a subtle delicacy, while his public persona was combative. He found a parallel between painting and music and entitled many of his paintings "arrangements", "harmonies", and "nocturnes", emphasising the primacy of tonal harmony.